The present invention relates to ganged mowing machines in general, and more specifically to a hydraulically driven, self-propelled, ganged mowing machine with a vertically adjustable mower platform for particular use in cutting or pruning nursery products, such as shrubs, bushes, and the like.
A number of ganged mowing machines have been proposed in the past. The majority of these machines have been directed towards cutting large expanses of grass upon golf courses, parks, large estates, and roadsides. Typically, these machines are intended to be towed by a tractor where a power-take-off unit from the tractor provides the power required to run the mowers. A typical example of a towed ganged mower is U.S. Pat. No. 5,069,022 entitled xe2x80x9cGang Mower Apparatus,xe2x80x9d issued to Vandermark. This device features nine rotary mowers attached to a frame which is towed behind a tractor. The mowers are mechanically driven by means of shafts and belts via a mechanical power-take-off from the tractor. Each mower unit is liftable from a cutting position to a travel position via a hydraulic cylinder. By lifting the mower units during periods of travel between mowing sites, the trailer may be towed at a faster rate of speed than if the mower units were left in the cutting position. Hydraulic power to drive the lifting cylinders is provided via a fluid-power-take-off from the tractor. Each mower unit is designed to be independently movable with respect to the other mower units in order for each unit to more closely follow the terrain to be cut. The vertical height of the mowers with respect to the ground may be adjusted within a range of a few inches via an adjustable swivel wheel.
Ganged mowing machines of this type are unsuitable for the special needs of cutting nursery products. On a large expanse of lawn, a tractor may proceed directly in front of the mowers while cutting the grass without harming the lawn. This is not possible in a nursery setting as the tractor would crush the bushes and shrubs to be cut. In addition, towed mowers of the type discussed above have a limited vertical height adjustment. Typically, these mowers are designed to cut grass to a height of about one to three inches above the ground. While this is a desirable feature in cutting lawns, it is entirely unsuitable to cutting shrubs, bushes and other nursery products which often require trimming at a height within a range of two to three feet from the ground. Further, towed mowing machines typically suspend the mowers independently of each other so that the mower may closely follow the terrain. Again, while this feature is desirable in a grass cutting machine, it is undesirable in cutting nursery products. Nursery products are typically arranged in rows and are often potted. This arrangement renders independently suspended mowers impractical because the multiplicity of wheels and suspension members required would destroy or otherwise severely damage the nursery products.
Related machines such as xe2x80x9cridingxe2x80x9d lawn mowers are also known in the art. Some of these machines may incorporate more than one rotary mower blade. However, machines of this type suffer most of the same disadvantages associated with towed ganged mowers. What is needed needs of cutting or trimming nursery products. Ideally, such a therefore is a ganged mowing machine specifically developed for the machine would have a horizontal platform on which is mounted an array of ganged mowers. The platform should be comparatively wide so that the a large number of rows of nursery products may be cut or trimmed at one time. The mowing machine should have wheels only at the extreme ends of the platform to avoid trampling the shrubs, bushes, or plants to be cut. In addition, the mowing machine should be self-propelled to eliminate the need for a tractor. Further, the machine should be designed so that the mowers may adjust to a vertical height up to about three feet from the ground.
The exemplary embodiment of the present invention is a self propelled, steerable, vertically adjustable, hydraulicly driven, ganged mowing machine for cutting or trimming nursery products, such as shrubs, bushes, plants, and the like. The machine generally includes a rectangular horizontal platform where the platform supports a staggered array of mower decks and the machine""s power and control devices. Each mower deck includes a hydraulic motor which is operatively connected to a mower blade for cutting or trimming nursery products. Preferably, the platform is comparatively long in width and comparatively short in depth.
The exemplary embodiment of the mowing machine further includes right and left vertical frame assemblies. The horizontal or mower platform is slidably connected to each frame assembly on its right and left sides respectively via a pair of slideways. The slideways include a pair of slides on each frame assembly and carriages mounted on the platform, where the carriages fit about the slides. Each vertical frame assembly is also interconnected with the platform via a hydraulic cylinder. The hydraulic cylinders are used to adjust the platform, and the mower decks mounted thereon, with respect to the ground. Each vertical frame assembly includes an independently controllable hydraulically driven traction drive motor operably connected to a drive wheel for propelling the machine. The mowing machine may be steered by increasing or decreasing the speed of one drive wheel relative to the other drive wheel.
As stated, in the exemplary embodiment, the platform carries the power and control devices for driving the machine""s hydraulic systems. In general, these devices include a gasoline engine or prime mover. The prime mover drives a number of hydraulic pumps. At least one of the hydraulic pumps drives the hydraulic motors which drive the mower blades. At least one pump drives the traction motors mounted on the vertical frames, and at least one pump drives the hydraulic cylinders for raising the platform. The mowing machine also includes a seat for a driver, and controls for operating the gas engine, traction motors, and for engaging the mowers. The mowing machine is self-braking. These and other features of the invention will become more apparent from the following detailed description of the invention, when taken in conjunction with the accompanying exemplary drawings.